The present invention generally relates to a combined camera and viewer for use in connection with photography, and particularly with micro photographic records.
More specifically, the present invention relates to a self-contained apparatus in which micro photographic records of image information can be conveniently formed on a length of strip film and/or micro photographic records formed on a length of strip film can readily and conveniently examined or projected in enlarged image.
The term "image information" employed in the specification and claims is to be understood as including an arrangement of alphanumeric characters with or without pictorial representation, an arrangement of figures, and any other pieces of information reproduced or reproducible by means of a photographic technique.
Hitherto, a microfilm apparatus has been largely employed in practice as an apparatus for recording the image information on a microfilm. The microfilm is provided with either silver halide emulsion or diazo pigment and is generally used in the form of a roll of strip film, a microfiche, or an apertured cards.
On the other hand, an electrophotographic technique has been developed recently and has proved effective to form a high resolution of image on a transparent film. An electrophotographic microfilm system utilizing the electrophotographic technique is disclosed in, for example, Japanese Laid-open Patent Publication No. 58-149572, published Sept. 5, 1983. The electrophotographic system disclosed therein is a self-contained apparatus having four capabilities operable one at a time. These capabilities include a camera capability by which the image information can be photographically exposed on the microfilm, a processor capability by which the microfilm exposed to an image-wise light can be developed and fixed to render the image information so recorded photographically visible to the naked eyes, a reader capability by which the image information developed can be projected on an enlarged scale onto a built-in screen, and an information retrieving capability by which a desired frame of the microfilm can be readily retrieved immediately upon demand. This electrophotographic microfilm system has a number of advantages in that the photographic recording and developing of the image can be sequentially performed in situ, and the projection of the image information on an enlarged scale onto the built-in screen to be viewed by the operator can be carried immediately after the fixing of the microfilm. In addition, not only can the retrieval and projection of the image information recorded on a randomly chosen frame of the microfilm be possible, but also the image information can be photographically recorded on a purposely or purposelessly chosen frame of the microfilm. Moreover, the system is compact in structure as much as it can be placed on the top of an office desk and is, therefore, utilizeable as a data file.
A specific example of the above described microfilm system is shown in FIGS. 1 to 5. The electrophotographic microfilm system has such an outer appearance as shown in FIG. 1 and has a foldable lid 2 which, when the system is in use, is pivoted to an opened position as shown in FIG. 2 to form an optical system utilizeable during the exposure (i.e., photographically recording the image information on the microfilm) and the projection of the image information. The electrophotographic microfilm (hereinafter referred to as "microfilm" for the sake of brevity) is accommodated in a two-reeled cassette 3 such as shown in FIG. 3, said cassette 3 being adapted to be set in a cassette holder 4 shown in FIG. 2. Within the cassette 3, as shown in FIG. 4, a length of magnetic recording tape 6 is connected at one end to a hub 5, and a length of rolled microfilm 8 is connected at one end to another hub 7, the length of magnetic recording tape 6 and the length of rolled microfilm 8 having their respective opposite ends connected together to provide a single length of tape 9. The length of tape 9 has a width of, for example, 16 mm, and has a row of blip markings 10 formed on one of the opposite edge portions thereof in a direction lengthwise of the tape 9. The blip markings 10 are used for the detection of a frame address (it being, however, noted that it may happen that the blip markings is used for the control of a position at which a frame is brought to a halt).
The length of tape 9 is transported by a direct current motor 11 in one of the opposite directions lengthwise thereof as shown in FIG. 5. When the image information is desired to be photographically recorded, an original bearing the image information is placed on a transparent support 12 which concurrently serves as a screen. The original placed on the support 12 is illuminated by an illuminator lamp 13 with an image-wise light being consequently reflected from the original on the support -2. This image-wise light is then projected through spaced reflecting mirrors 14 and 15 and then through a lens assembly 16 onto one of the frames then positioned at a charging and exposure chamber. After the exposure, the length of tape 9 is passed frame by frame through a processing head 17, provided with a developing chamber and a drying chamber, so as to permit the exposed frame or frames to be automatically developed. The processing head employed may be the one disclosed in, for example, application Ser. No. 585,932, filed Mar. 5, 1984, or application Ser. No. 575,522 filed Feb. 9, 1984.
The frame in which the image has been developed is held at a predetermined position (within the charging and exposure chamber) of the processing head 17 and, if it is illuminated by a projector lamp 18 through a mirror 19 and a condenser lens 20, the resultant image-wise light can be projected through the lens assembly 16 and then through the mirrors 15 and 14 onto the combined support and screen 12 with the image consequently reproduced on an enlarged scale.
Information concerning the image electrophotographically recorded in the manner described above is stored, on piecemeal basis, in a storage means 21 which is built in the apparatus and which may comprise a write-in/write-out storage means, for example, a semiconductor memory, and, after the completion of a required processing, is automatically recorded on the length of magnetic recording tape 6 by a magnetic recording head 25 on frame-to-frame basis. During the subsequent use, the contents recorded on the length of magnetic tape 6 are read out by another magnetic head 22 secured to the tip of an arm and are then read in the storage means. Various control functions are executed by an electronic control means (for example, a digital logic circuit or an analog circuit) having a microprocessor or a microcomputer constituting the heart thereof), built in the apparatus, on the basis of the data stored in the storage means 21 and external data and commands, and, on the other hand, operating commands are provided by operating various switches arranged on a control panel 23.
In the combined camera and viewer of the construction described above, since the recording and the projection of the image information can be performed one at a time, at any time and in any manner as desired by the operator, there is the possibilities that an unexposed frame or frames may be exposed to light emitted from the projector lamp and that a once-exposed frame may again be exposed to the image-wise light. In the former case, the electrophotographic film is susceptible to exhaustion due to exposure to light to such an extent as to result in the reduced contrast of an image subsequently photographed, and in the latter case, double exposure takes place with the consequence that the previously photographed image is destroyed.